mongo 数据库提前关闭 避免读写任务没有结束，异步任务没有完成，同步指令提前关闭数据库：'MongoError: server instance pool was destroyed'

mongo 数据库提前关闭  

// mongodb - npm https://www.npmjs.com/package/mongodb
const mongoCfg = {
    uri: 'mongodb://hbaseU:123@192.168.3.103:27017/hbase',
    dbName: 'hbase',
    collectionName: 'todayUrlsTmpURL'
}

const MongoClient = require('mongodb').MongoClient
// npm install assert
const assert = require('assert')
// Use connect method to connect to the server

MongoClient.connect(mongoCfg.uri, function (err, client) {
    assert.equal(null, err)
    console.log('Connected successfully to server')
    const db = client.db(mongoCfg.dbName)
    const collectionName = mongoCfg.collectionName
    findDocuments(db, collectionName, {}, function (docs) {
        for (let i in docs) {
            const ii = docs[i]
            let mgid = ii._id
            let filter = {
                _id: mgid
            }
            console.log(filter)
            let val = {
                $set: {
                    url: 's'
                }
            }
            updateDocument(db, collectionName, filter, val, function (result) {
                console.log(result)
            })
        }
    })
    client.close()
})

const findDocuments = function (db, collectionName, filter, callback) {
    // Get the documents collection
    const collection = db.collection(collectionName)
    // Find some documents
    collection.find(filter).toArray(function (err, docs) {
        assert.equal(err, null)
        console.log("Found the following records")
        console.log(docs.length)
        callback(docs)
    })
}

const updateDocument = function (db, collectionName, filter, val, callback) {
    // Get the documents collection
    const collection = db.collection(collectionName)
    collection.updateOne(filter, val, function (err, result) {
        console.log(err)
        assert.equal(err, null)
        assert.equal(1, result.result.n)
        callback(result)
    })
}

// mongodb - npm https://www.npmjs.com/package/mongodb

const mongoCfg = {

uri: 'mongodb://hbaseU:123@192.168.3.103:27017/hbase',

dbName: 'hbase',

collectionName: 'todayUrlsTmpURL'

}

const MongoClient = require('mongodb').MongoClient

// npm install assert

const assert = require('assert')

// Use connect method to connect to the server

MongoClient.connect(mongoCfg.uri, function (err, client) {

assert.equal(null, err)

console.log('Connected successfully to server')

const db = client.db(mongoCfg.dbName)

const collectionName = mongoCfg.collectionName

findDocuments(db, collectionName, {}, function (docs) {

for (let i in docs) {

const ii = docs[i]

let mgid = ii._id

let filter = {

_id: mgid

}

console.log(filter)

let val = {

$set: {

url: 'ok-' + mgid

}

}

updateDocument(db, collectionName, filter, val, function (result) {

console.log(result)

})

}

// 在回调中关闭数据库

// 保证读写完全结束后关闭数据库

// 以与之（读写完全结束）同步的方式关闭数据库

client.close()

})

// 避免读写任务没有结束，异步任务没有完成，同步指令提前关闭数据库：'MongoError: server instance pool was destroyed'

// client.close()

})

const findDocuments = function (db, collectionName, filter, callback) {

// Get the documents collection

const collection = db.collection(collectionName)

// Find some documents

collection.find(filter).toArray(function (err, docs) {

assert.equal(err, null)

console.log("Found the following records")

console.log(docs.length)

callback(docs)

})

}

const updateDocument = function (db, collectionName, filter, val, callback) {

// Get the documents collection

const collection = db.collection(collectionName)

collection.updateOne(filter, val, function (err, result) {

console.log(err)

assert.equal(err, null)

assert.equal(1, result.result.n)

callback(result)

})

}

 

// mongodb - npm https://www.npmjs.com/package/mongodb
const mongoCfg = {
    uri: 'mongodb://hbaseU:123@192.168.3.103:27017/hbase',
    dbName: 'hbase',
    collectionName: 'todayUrlsTmpURL'
}

const MongoClient = require('mongodb').MongoClient
// npm install assert
const assert = require('assert')
// Use connect method to connect to the server
MongoClient.connect(mongoCfg.uri, function (err, client) {
    assert.equal(null, err)
    console.log('Connected successfully to server')
    const db = client.db(mongoCfg.dbName)
    const collectionName = mongoCfg.collectionName
    findDocuments(db, collectionName, {}, function (docs) {
        for (let i in docs) {
            const ii = docs[i]
            let mgid = ii._id
            let filter = {
                _id: mgid
            }
            console.log(filter)
            let val = {
                $set: {
                    url: 'ok-' + mgid
                }
            }
            updateDocument(db, collectionName, filter, val, function (result) {
                console.log(result)
            })
        }
        // 在回调中关闭数据库
        // 保证读写完全结束后关闭数据库
        // 以与之（读写完全结束）同步的方式关闭数据库
        client.close()
    })
    // 避免读写任务没有结束，异步任务没有完成，同步指令提前关闭数据库：'MongoError: server instance pool was destroyed'
    // client.close()
})

const findDocuments = function (db, collectionName, filter, callback) {
    // Get the documents collection
    const collection = db.collection(collectionName)
    // Find some documents
    collection.find(filter).toArray(function (err, docs) {
        assert.equal(err, null)
        console.log("Found the following records")
        console.log(docs.length)
        callback(docs)
    })
}

const updateDocument = function (db, collectionName, filter, val, callback) {
    // Get the documents collection
    const collection = db.collection(collectionName)
    collection.updateOne(filter, val, function (err, result) {
        console.log(err)
        assert.equal(err, null)
        assert.equal(1, result.result.n)
        callback(result)
    })
}